electro-acoustic transducer that converts electrical signals into sounds loud enough to be heard at a distance | a social or business visitor |
someone who expresses in language; someone who talks (especially someone who delivers a public speech or someone especially garrulous) | the person initiating a telephone call |
| the person who convenes a meeting |
| someone who proclaims or summons in a loud voice |
| a person who announces the changes of steps during a dance |
| the bettor in a card game who matches the bet and calls for a show of hands |
| an investor who buys a call option |